01 / How do I open .dcm files?

How do I open .dcm files?#

  1. Keep the complete original folder tree, including DICOMDIR and all referenced image subfolders if supplied. Do not move or rename its files.
  2. Visit https://openmyscan.com in any browser (Chrome, Safari, Edge, or Firefox).
  3. Drag the folder onto the drop zone. OpenMyScan assembles the stack locally; nothing uploads by default.
02 / Step 1 — Treat the folder as the unit, not one icon

Step 1 — Treat the folder as the unit, not one icon#

Double-clicking a lone .dcm in macOS Preview or Windows Photos fails because those apps expect vacation photos. Medical viewers read the whole directory so slice order, spacing, and orientation stay correct.

03 / Step 2 — Copy before you open from slow media

Step 2 — Copy before you open from slow media#

If the files live on a CD or network drive, copy the folder to your Desktop first. Browsers read thousands of small files faster from an internal SSD, and some corporate laptops block optical drives entirely.

04 / Step 3 — Scroll and sanity-check

Step 3 — Scroll and sanity-check#

After the progress bar finishes, use the slice slider or left/right arrow keys to move through slices. In single view, the mouse wheel zooms. If a series list appears, click each entry. Some studies bundle multiple directions (axial, sagittal, coronal). Our free DICOM viewer handles each of those orientations natively. Brightness still needs a radiologist's eye; OpenMyScan is not diagnosing you.

05 / Why won't a .dcm file open on Mac or Windows?

Why won't a .dcm file open on Mac or Windows?#

Someone emailed a single tiny .dcm
Ask for the complete original study; one file may contain only part of it.
Files have no .dcm suffix
That is normal; OpenMyScan reads the file header to detect DICOM instead of relying on filenames.
Drag-and-drop does nothing
Use the folder picker button or try another browser; some locked-down PCs block drag.
I see DICOMDIR but the screen stays blank
Copy the complete original directory tree, keeping DICOMDIR and all referenced subfolders in their supplied locations. Select the parent folder; do not move image files beside the index.
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06 / Common questions

Common questions#

Is .dcm the same as DICOM?

Yes. DICOM is the standard, .dcm is the most common file extension for it. .dic, .dicom, and no-extension files also occur.

What software do radiologists use?

Horos, OsiriX, RadiAnt, Weasis are clinical tools with mass/measurement features. OpenMyScan is the patient-friendly version: same files, simpler UI.

Can I convert .dcm to JPEG?

Yes. OpenMyScan exports any slice as PNG or JPEG, no account or upgrade needed. Open the file, pick the slice, choose Export.

Can I view my scan on my phone?

No. The viewer needs a browser window at least 1200 pixels wide to show images alongside the series list. Use a laptop or desktop, or a tablet only if its browser window meets that width. Rotating an iPad to landscape does not guarantee enough space. Guides remain available on smaller screens.

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